Rules of game for eastern European countries willing to join euro zone has just changed, Bloomberg reports.

Bulgaria is the latest country from post-communist area, which expressed desire to enter single currency bloc and received approval from EU to proceed with necessary steps. However, conditions for entering will be stricter than for other recent new entrants. New rules will apply to Croatia and Romania that are ready to follow after Bulgaria.

Bulgaria meets all the necessary formal conditions and thought that it is very close to its goal. However, taking into account last scandals with money laundering, such as one in Latvia, which entered euro area recently, EU decided to tighten conditions for entry. New demands include cooperation with banking union of the bloc and steps to restrict corruption.